1. Field of the invention
The present invention relates to stabilized supplies, generally used for constant voltage or constant current supply of electronic circuits, in particular electronic circuits and devices during testing thereof.
2. Description of the prior art
Stabilized power supplies are well known instruments, and are largely employed in R & D and in test laboratories for arranging preset test conditions of devices and electronic circuits. Often these supplies, wherein it is generally possible to manually set by means of appropriate controls a desired output constant voltage or current, are also provided with a control terminal to which a control voltage may be applied in order to automatically set the desired value of the constant output voltage or current. In complex testing procedures, the control of the supply voltages and/or of the supply currents delivered by one or more stabilized power supplies to the devices being tested may be performed by a central processing unit (CPU).
If during the carrying out of a test procedure the power is momentarily interrupted, when the latter is reestablished, the power supplies are reactivated and deliver across their output terminals the voltages which had been set previously. These voltages will become available at the respective output terminals abruptly causing a voltage peaking (and/or a current peaking) which may negatively affect the reliability of the test results and often damage delicate devices which are powered by these stabilized supplies.
Certain problems caused by accidental power interruptions, may be particularly serious when performing "life test" procedures of an integrated reliability test program, wherein the stability of the supply voltage and of the dynamic signals applied to the devices under test becomes extremely important. This may the case of a back-end testing of micrologics (integrated logic devices) with a high level of integration.